]> git.ipfire.org Git - thirdparty/systemd.git/blob - src/basic/macro.h
4d33e702829cea42a582e82d5d75a9dd5504cc39
[thirdparty/systemd.git] / src / basic / macro.h
1 /* SPDX-License-Identifier: LGPL-2.1+ */
2 #pragma once
3
4 /***
5 Copyright 2010 Lennart Poettering
6 ***/
7
8 #include <inttypes.h>
9 #include <stdbool.h>
10 #include <sys/param.h>
11 #include <sys/sysmacros.h>
12 #include <sys/types.h>
13
14 #define _printf_(a,b) __attribute__ ((format (printf, a, b)))
15 #ifdef __clang__
16 # define _alloc_(...)
17 #else
18 # define _alloc_(...) __attribute__ ((alloc_size(__VA_ARGS__)))
19 #endif
20 #define _sentinel_ __attribute__ ((sentinel))
21 #define _unused_ __attribute__ ((unused))
22 #define _destructor_ __attribute__ ((destructor))
23 #define _pure_ __attribute__ ((pure))
24 #define _const_ __attribute__ ((const))
25 #define _deprecated_ __attribute__ ((deprecated))
26 #define _packed_ __attribute__ ((packed))
27 #define _malloc_ __attribute__ ((malloc))
28 #define _weak_ __attribute__ ((weak))
29 #define _likely_(x) (__builtin_expect(!!(x),1))
30 #define _unlikely_(x) (__builtin_expect(!!(x),0))
31 #define _public_ __attribute__ ((visibility("default")))
32 #define _hidden_ __attribute__ ((visibility("hidden")))
33 #define _weakref_(x) __attribute__((weakref(#x)))
34 #define _alignas_(x) __attribute__((aligned(__alignof(x))))
35 #define _cleanup_(x) __attribute__((cleanup(x)))
36 #if __GNUC__ >= 7
37 #define _fallthrough_ __attribute__((fallthrough))
38 #else
39 #define _fallthrough_
40 #endif
41 /* Define C11 noreturn without <stdnoreturn.h> and even on older gcc
42 * compiler versions */
43 #ifndef _noreturn_
44 #if __STDC_VERSION__ >= 201112L
45 #define _noreturn_ _Noreturn
46 #else
47 #define _noreturn_ __attribute__((noreturn))
48 #endif
49 #endif
50
51 #if !defined(HAS_FEATURE_MEMORY_SANITIZER)
52 # if defined(__has_feature)
53 # if __has_feature(memory_sanitizer)
54 # define HAS_FEATURE_MEMORY_SANITIZER 1
55 # endif
56 # endif
57 # if !defined(HAS_FEATURE_MEMORY_SANITIZER)
58 # define HAS_FEATURE_MEMORY_SANITIZER 0
59 # endif
60 #endif
61
62 /* Temporarily disable some warnings */
63 #define DISABLE_WARNING_DECLARATION_AFTER_STATEMENT \
64 _Pragma("GCC diagnostic push"); \
65 _Pragma("GCC diagnostic ignored \"-Wdeclaration-after-statement\"")
66
67 #define DISABLE_WARNING_FORMAT_NONLITERAL \
68 _Pragma("GCC diagnostic push"); \
69 _Pragma("GCC diagnostic ignored \"-Wformat-nonliteral\"")
70
71 #define DISABLE_WARNING_MISSING_PROTOTYPES \
72 _Pragma("GCC diagnostic push"); \
73 _Pragma("GCC diagnostic ignored \"-Wmissing-prototypes\"")
74
75 #define DISABLE_WARNING_NONNULL \
76 _Pragma("GCC diagnostic push"); \
77 _Pragma("GCC diagnostic ignored \"-Wnonnull\"")
78
79 #define DISABLE_WARNING_SHADOW \
80 _Pragma("GCC diagnostic push"); \
81 _Pragma("GCC diagnostic ignored \"-Wshadow\"")
82
83 #define DISABLE_WARNING_INCOMPATIBLE_POINTER_TYPES \
84 _Pragma("GCC diagnostic push"); \
85 _Pragma("GCC diagnostic ignored \"-Wincompatible-pointer-types\"")
86
87 #define REENABLE_WARNING \
88 _Pragma("GCC diagnostic pop")
89
90 /* automake test harness */
91 #define EXIT_TEST_SKIP 77
92
93 #define XSTRINGIFY(x) #x
94 #define STRINGIFY(x) XSTRINGIFY(x)
95
96 #define XCONCATENATE(x, y) x ## y
97 #define CONCATENATE(x, y) XCONCATENATE(x, y)
98
99 #define UNIQ_T(x, uniq) CONCATENATE(__unique_prefix_, CONCATENATE(x, uniq))
100 #define UNIQ __COUNTER__
101
102 /* builtins */
103 #if __SIZEOF_INT__ == 4
104 #define BUILTIN_FFS_U32(x) __builtin_ffs(x);
105 #elif __SIZEOF_LONG__ == 4
106 #define BUILTIN_FFS_U32(x) __builtin_ffsl(x);
107 #else
108 #error "neither int nor long are four bytes long?!?"
109 #endif
110
111 /* Rounds up */
112
113 #define ALIGN4(l) (((l) + 3) & ~3)
114 #define ALIGN8(l) (((l) + 7) & ~7)
115
116 #if __SIZEOF_POINTER__ == 8
117 #define ALIGN(l) ALIGN8(l)
118 #elif __SIZEOF_POINTER__ == 4
119 #define ALIGN(l) ALIGN4(l)
120 #else
121 #error "Wut? Pointers are neither 4 nor 8 bytes long?"
122 #endif
123
124 #define ALIGN_PTR(p) ((void*) ALIGN((unsigned long) (p)))
125 #define ALIGN4_PTR(p) ((void*) ALIGN4((unsigned long) (p)))
126 #define ALIGN8_PTR(p) ((void*) ALIGN8((unsigned long) (p)))
127
128 static inline size_t ALIGN_TO(size_t l, size_t ali) {
129 return ((l + ali - 1) & ~(ali - 1));
130 }
131
132 #define ALIGN_TO_PTR(p, ali) ((void*) ALIGN_TO((unsigned long) (p), (ali)))
133
134 /* align to next higher power-of-2 (except for: 0 => 0, overflow => 0) */
135 static inline unsigned long ALIGN_POWER2(unsigned long u) {
136 /* clz(0) is undefined */
137 if (u == 1)
138 return 1;
139
140 /* left-shift overflow is undefined */
141 if (__builtin_clzl(u - 1UL) < 1)
142 return 0;
143
144 return 1UL << (sizeof(u) * 8 - __builtin_clzl(u - 1UL));
145 }
146
147 #ifndef __COVERITY__
148 # define VOID_0 ((void)0)
149 #else
150 # define VOID_0 ((void*)0)
151 #endif
152
153 #define ELEMENTSOF(x) \
154 __extension__ (__builtin_choose_expr( \
155 !__builtin_types_compatible_p(typeof(x), typeof(&*(x))), \
156 sizeof(x)/sizeof((x)[0]), \
157 VOID_0))
158
159 /*
160 * STRLEN - return the length of a string literal, minus the trailing NUL byte.
161 * Contrary to strlen(), this is a constant expression.
162 * @x: a string literal.
163 */
164 #define STRLEN(x) (sizeof(""x"") - 1)
165
166 /*
167 * container_of - cast a member of a structure out to the containing structure
168 * @ptr: the pointer to the member.
169 * @type: the type of the container struct this is embedded in.
170 * @member: the name of the member within the struct.
171 */
172 #define container_of(ptr, type, member) __container_of(UNIQ, (ptr), type, member)
173 #define __container_of(uniq, ptr, type, member) \
174 __extension__ ({ \
175 const typeof( ((type*)0)->member ) *UNIQ_T(A, uniq) = (ptr); \
176 (type*)( (char *)UNIQ_T(A, uniq) - offsetof(type,member) ); \
177 })
178
179 #undef MAX
180 #define MAX(a, b) __MAX(UNIQ, (a), UNIQ, (b))
181 #define __MAX(aq, a, bq, b) \
182 __extension__ ({ \
183 const typeof(a) UNIQ_T(A, aq) = (a); \
184 const typeof(b) UNIQ_T(B, bq) = (b); \
185 UNIQ_T(A,aq) > UNIQ_T(B,bq) ? UNIQ_T(A,aq) : UNIQ_T(B,bq); \
186 })
187
188 /* evaluates to (void) if _A or _B are not constant or of different types */
189 #define CONST_MAX(_A, _B) \
190 __extension__ (__builtin_choose_expr( \
191 __builtin_constant_p(_A) && \
192 __builtin_constant_p(_B) && \
193 __builtin_types_compatible_p(typeof(_A), typeof(_B)), \
194 ((_A) > (_B)) ? (_A) : (_B), \
195 VOID_0))
196
197 /* takes two types and returns the size of the larger one */
198 #define MAXSIZE(A, B) (sizeof(union _packed_ { typeof(A) a; typeof(B) b; }))
199
200 #define MAX3(x,y,z) \
201 __extension__ ({ \
202 const typeof(x) _c = MAX(x,y); \
203 MAX(_c, z); \
204 })
205
206 #undef MIN
207 #define MIN(a, b) __MIN(UNIQ, (a), UNIQ, (b))
208 #define __MIN(aq, a, bq, b) \
209 __extension__ ({ \
210 const typeof(a) UNIQ_T(A, aq) = (a); \
211 const typeof(b) UNIQ_T(B, bq) = (b); \
212 UNIQ_T(A,aq) < UNIQ_T(B,bq) ? UNIQ_T(A,aq) : UNIQ_T(B,bq); \
213 })
214
215 #define MIN3(x,y,z) \
216 __extension__ ({ \
217 const typeof(x) _c = MIN(x,y); \
218 MIN(_c, z); \
219 })
220
221 #define LESS_BY(a, b) __LESS_BY(UNIQ, (a), UNIQ, (b))
222 #define __LESS_BY(aq, a, bq, b) \
223 __extension__ ({ \
224 const typeof(a) UNIQ_T(A, aq) = (a); \
225 const typeof(b) UNIQ_T(B, bq) = (b); \
226 UNIQ_T(A,aq) > UNIQ_T(B,bq) ? UNIQ_T(A,aq) - UNIQ_T(B,bq) : 0; \
227 })
228
229 #undef CLAMP
230 #define CLAMP(x, low, high) __CLAMP(UNIQ, (x), UNIQ, (low), UNIQ, (high))
231 #define __CLAMP(xq, x, lowq, low, highq, high) \
232 __extension__ ({ \
233 const typeof(x) UNIQ_T(X,xq) = (x); \
234 const typeof(low) UNIQ_T(LOW,lowq) = (low); \
235 const typeof(high) UNIQ_T(HIGH,highq) = (high); \
236 UNIQ_T(X,xq) > UNIQ_T(HIGH,highq) ? \
237 UNIQ_T(HIGH,highq) : \
238 UNIQ_T(X,xq) < UNIQ_T(LOW,lowq) ? \
239 UNIQ_T(LOW,lowq) : \
240 UNIQ_T(X,xq); \
241 })
242
243 /* [(x + y - 1) / y] suffers from an integer overflow, even though the
244 * computation should be possible in the given type. Therefore, we use
245 * [x / y + !!(x % y)]. Note that on "Real CPUs" a division returns both the
246 * quotient and the remainder, so both should be equally fast. */
247 #define DIV_ROUND_UP(_x, _y) \
248 __extension__ ({ \
249 const typeof(_x) __x = (_x); \
250 const typeof(_y) __y = (_y); \
251 (__x / __y + !!(__x % __y)); \
252 })
253
254 #define assert_message_se(expr, message) \
255 do { \
256 if (_unlikely_(!(expr))) \
257 log_assert_failed(message, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
258 } while (false)
259
260 #define assert_se(expr) assert_message_se(expr, #expr)
261
262 /* We override the glibc assert() here. */
263 #undef assert
264 #ifdef NDEBUG
265 #define assert(expr) do {} while (false)
266 #else
267 #define assert(expr) assert_message_se(expr, #expr)
268 #endif
269
270 #define assert_not_reached(t) \
271 do { \
272 log_assert_failed_unreachable(t, __FILE__, __LINE__, __PRETTY_FUNCTION__); \
273 } while (false)
274
275 #if defined(static_assert)
276 /* static_assert() is sometimes defined in a way that trips up
277 * -Wdeclaration-after-statement, hence let's temporarily turn off
278 * this warning around it. */
279 #define assert_cc(expr) \
280 DISABLE_WARNING_DECLARATION_AFTER_STATEMENT; \
281 static_assert(expr, #expr); \
282 REENABLE_WARNING
283 #else
284 #define assert_cc(expr) \
285 DISABLE_WARNING_DECLARATION_AFTER_STATEMENT; \
286 struct CONCATENATE(_assert_struct_, __COUNTER__) { \
287 char x[(expr) ? 0 : -1]; \
288 }; \
289 REENABLE_WARNING
290 #endif
291
292 #define assert_log(expr, message) ((_likely_(expr)) \
293 ? (true) \
294 : (log_assert_failed_return(message, __FILE__, __LINE__, __PRETTY_FUNCTION__), false))
295
296 #define assert_return(expr, r) \
297 do { \
298 if (!assert_log(expr, #expr)) \
299 return (r); \
300 } while (false)
301
302 #define assert_return_errno(expr, r, err) \
303 do { \
304 if (!assert_log(expr, #expr)) { \
305 errno = err; \
306 return (r); \
307 } \
308 } while (false)
309
310 #define PTR_TO_INT(p) ((int) ((intptr_t) (p)))
311 #define INT_TO_PTR(u) ((void *) ((intptr_t) (u)))
312 #define PTR_TO_UINT(p) ((unsigned int) ((uintptr_t) (p)))
313 #define UINT_TO_PTR(u) ((void *) ((uintptr_t) (u)))
314
315 #define PTR_TO_LONG(p) ((long) ((intptr_t) (p)))
316 #define LONG_TO_PTR(u) ((void *) ((intptr_t) (u)))
317 #define PTR_TO_ULONG(p) ((unsigned long) ((uintptr_t) (p)))
318 #define ULONG_TO_PTR(u) ((void *) ((uintptr_t) (u)))
319
320 #define PTR_TO_INT32(p) ((int32_t) ((intptr_t) (p)))
321 #define INT32_TO_PTR(u) ((void *) ((intptr_t) (u)))
322 #define PTR_TO_UINT32(p) ((uint32_t) ((uintptr_t) (p)))
323 #define UINT32_TO_PTR(u) ((void *) ((uintptr_t) (u)))
324
325 #define PTR_TO_INT64(p) ((int64_t) ((intptr_t) (p)))
326 #define INT64_TO_PTR(u) ((void *) ((intptr_t) (u)))
327 #define PTR_TO_UINT64(p) ((uint64_t) ((uintptr_t) (p)))
328 #define UINT64_TO_PTR(u) ((void *) ((uintptr_t) (u)))
329
330 #define PTR_TO_SIZE(p) ((size_t) ((uintptr_t) (p)))
331 #define SIZE_TO_PTR(u) ((void *) ((uintptr_t) (u)))
332
333 #define CHAR_TO_STR(x) ((char[2]) { x, 0 })
334
335 #define char_array_0(x) x[sizeof(x)-1] = 0;
336
337 /* Returns the number of chars needed to format variables of the
338 * specified type as a decimal string. Adds in extra space for a
339 * negative '-' prefix (hence works correctly on signed
340 * types). Includes space for the trailing NUL. */
341 #define DECIMAL_STR_MAX(type) \
342 (2+(sizeof(type) <= 1 ? 3 : \
343 sizeof(type) <= 2 ? 5 : \
344 sizeof(type) <= 4 ? 10 : \
345 sizeof(type) <= 8 ? 20 : sizeof(int[-2*(sizeof(type) > 8)])))
346
347 #define DECIMAL_STR_WIDTH(x) \
348 ({ \
349 typeof(x) _x_ = (x); \
350 unsigned ans = 1; \
351 while ((_x_ /= 10) != 0) \
352 ans++; \
353 ans; \
354 })
355
356 #define SET_FLAG(v, flag, b) \
357 (v) = (b) ? ((v) | (flag)) : ((v) & ~(flag))
358 #define FLAGS_SET(v, flags) \
359 (((v) & (flags)) == (flags))
360
361 #define CASE_F(X) case X:
362 #define CASE_F_1(CASE, X) CASE_F(X)
363 #define CASE_F_2(CASE, X, ...) CASE(X) CASE_F_1(CASE, __VA_ARGS__)
364 #define CASE_F_3(CASE, X, ...) CASE(X) CASE_F_2(CASE, __VA_ARGS__)
365 #define CASE_F_4(CASE, X, ...) CASE(X) CASE_F_3(CASE, __VA_ARGS__)
366 #define CASE_F_5(CASE, X, ...) CASE(X) CASE_F_4(CASE, __VA_ARGS__)
367 #define CASE_F_6(CASE, X, ...) CASE(X) CASE_F_5(CASE, __VA_ARGS__)
368 #define CASE_F_7(CASE, X, ...) CASE(X) CASE_F_6(CASE, __VA_ARGS__)
369 #define CASE_F_8(CASE, X, ...) CASE(X) CASE_F_7(CASE, __VA_ARGS__)
370 #define CASE_F_9(CASE, X, ...) CASE(X) CASE_F_8(CASE, __VA_ARGS__)
371 #define CASE_F_10(CASE, X, ...) CASE(X) CASE_F_9(CASE, __VA_ARGS__)
372 #define CASE_F_11(CASE, X, ...) CASE(X) CASE_F_10(CASE, __VA_ARGS__)
373 #define CASE_F_12(CASE, X, ...) CASE(X) CASE_F_11(CASE, __VA_ARGS__)
374 #define CASE_F_13(CASE, X, ...) CASE(X) CASE_F_12(CASE, __VA_ARGS__)
375 #define CASE_F_14(CASE, X, ...) CASE(X) CASE_F_13(CASE, __VA_ARGS__)
376 #define CASE_F_15(CASE, X, ...) CASE(X) CASE_F_14(CASE, __VA_ARGS__)
377 #define CASE_F_16(CASE, X, ...) CASE(X) CASE_F_15(CASE, __VA_ARGS__)
378 #define CASE_F_17(CASE, X, ...) CASE(X) CASE_F_16(CASE, __VA_ARGS__)
379 #define CASE_F_18(CASE, X, ...) CASE(X) CASE_F_17(CASE, __VA_ARGS__)
380 #define CASE_F_19(CASE, X, ...) CASE(X) CASE_F_18(CASE, __VA_ARGS__)
381 #define CASE_F_20(CASE, X, ...) CASE(X) CASE_F_19(CASE, __VA_ARGS__)
382
383 #define GET_CASE_F(_1,_2,_3,_4,_5,_6,_7,_8,_9,_10,_11,_12,_13,_14,_15,_16,_17,_18,_19,_20,NAME,...) NAME
384 #define FOR_EACH_MAKE_CASE(...) \
385 GET_CASE_F(__VA_ARGS__,CASE_F_20,CASE_F_19,CASE_F_18,CASE_F_17,CASE_F_16,CASE_F_15,CASE_F_14,CASE_F_13,CASE_F_12,CASE_F_11, \
386 CASE_F_10,CASE_F_9,CASE_F_8,CASE_F_7,CASE_F_6,CASE_F_5,CASE_F_4,CASE_F_3,CASE_F_2,CASE_F_1) \
387 (CASE_F,__VA_ARGS__)
388
389 #define IN_SET(x, ...) \
390 ({ \
391 bool _found = false; \
392 /* If the build breaks in the line below, you need to extend the case macros */ \
393 static _unused_ char _static_assert__macros_need_to_be_extended[20 - sizeof((int[]){__VA_ARGS__})/sizeof(int)]; \
394 switch(x) { \
395 FOR_EACH_MAKE_CASE(__VA_ARGS__) \
396 _found = true; \
397 break; \
398 default: \
399 break; \
400 } \
401 _found; \
402 })
403
404 #define SWAP_TWO(x, y) do { \
405 typeof(x) _t = (x); \
406 (x) = (y); \
407 (y) = (_t); \
408 } while (false)
409
410 /* Define C11 thread_local attribute even on older gcc compiler
411 * version */
412 #ifndef thread_local
413 /*
414 * Don't break on glibc < 2.16 that doesn't define __STDC_NO_THREADS__
415 * see http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53769
416 */
417 #if __STDC_VERSION__ >= 201112L && !(defined(__STDC_NO_THREADS__) || (defined(__GNU_LIBRARY__) && __GLIBC__ == 2 && __GLIBC_MINOR__ < 16))
418 #define thread_local _Thread_local
419 #else
420 #define thread_local __thread
421 #endif
422 #endif
423
424 #define DEFINE_TRIVIAL_CLEANUP_FUNC(type, func) \
425 static inline void func##p(type *p) { \
426 if (*p) \
427 func(*p); \
428 }
429
430 #include "log.h"